1. A: All living things have cells or cell.

B: Cells are like blocks for living things.

C: Activity of an organism depends on total activity of an independent cell.

D: Cells cme from cells.

2. cytoplasm,nucleus,cell membrane,vacuole,endoplasmic reticulum,mitochondria,cell wall,and chloroplasts.

3. cell walls and chloroplasts.

4. it protects the cell and transports food and water for the cell/cells.

5.long time ago before they had microscopes people thought that anything just came from the thin air because they couldn't see the cells.